The present invention relates to a building block system, particularly for the creation of separating walls, supporting walls, borders, and the like in gardens and parks.
In prior art building block systems of this type, the elements are put together without mortar. They engage one another by means of certain projections to hold the blocks together better and to simplify the laying of the blocks. For example, complementary projections and recesses may be provided at the upper and lower horizontal sides and/or at the lateral sides.
However, difficulties arise if the wall is to follow a bent course involving an angle of less than 90.degree.. In such a case, the wall cohesion normally resulting from the fact that the blocks of one course are offset longitudinally relative to the blocks of the adjacent courses is broken. Two wall sections standing at an angle to one another thus cannot be connected with one another unless special angle blocks are provided for the individual angle sizes.
British Patent 1,402,922 discloses a "keyhole" shaped building block which incorporates a bulbous, rounded portion and an essentially rectangular main portion having a concave socket region at one end to receive the bulbous portion of an adjacent block. This configuration permits the erection of a curved or arbitrarily angled wall as a continuous interconnected unit. However, this prior art building block is too small for landscaping applications and, if it were made suitably larger, it would not have sufficient stability since the width of the essentially rectangular main portion is significantly less than the diameter of the bulbous, rounded portion. The term "width" is here intended to mean the dimension perpendicular to the vertical sides of the blocks, a dimension which corresponds to the thickness of the wall.